Most states require that truck drivers use wheel chocks to prevent their vehicles from rolling during loading and unloading operations. Wheel chocks are triangular in cross section, often looking like miniature skateboard ramps, so as to be easily wedged under vehicle wheels. For maximum durability and grip upon a rolling surface, wheel chocks are made from metal, rubber, plastic, wood, and composites. To prevent their loss, wheel chocks are often brightly colored.
Aside from large trucks, wheel chocks can be beneficially used with cars, RVs, mobile homes, motorcycles, forklifts, and trailers. They provide a measure of safety while, for example, changing oil, fixing a flat tire, or performing other routine, maintenance work. Wheel chocks are light and small, and can be easily carried in vehicles of all sizes.
Using wheel chocks is simple, but not effortless. First, a driver stops his vehicle at a desired location and applies the vehicle's parking brakes. Then, he removes a chock from the storage compartment of the vehicle and slides it along the ground until wedged tightly against a wheel. After work is performed in, or around, the vehicle, a driver disengages the chock from the wheel by moving his vehicle forward few inches. The disengaged chock is, then, picked up and placed back in its storage compartment for reuse at a later time.
Some wheel chocks have been modified to reduce the amount of stooping required to use them. Some chocks, such as those typically seen at airports beneath jetliners, are provided with cords that can be pulled to free the chocks from wheels. Other chocks have been provided with elongated handles that serve a secondary purpose as markers of their presence. Unfortunately, these handled chocks have not seen widespread use since they have been prone to tip over and difficult to engage with more than one side of a vehicle wheel.